The present disclosure relates to a device and method for controlling a hybrid vehicle.
In a hybrid vehicle, vehicle vibrations may occur due to a sudden change in the engine torque when the operating state of the engine shifts from a load operation to an operation stop (fuel cutoff). The vehicle vibrations can be reduced by performing a self-sustaining operation (idle operation) before the operating state of the engine shifts from the load operation to the operation stop to reduce a change in the engine torque at the time of stopping the operation.
In the engine of a hybrid vehicle, a normal self-sustaining operation is performed in a state in which the engine torque is kept substantially zero. Therefore, when the self-sustaining operation before stoppage of the operation (hereinafter, referred to as pre-stoppage self-sustaining operation) is performed under the same condition as that of the normal self-sustaining operation (idle operation), fuel is consumed only for the self-sustaining operation of the engine. Japanese Laid-Open Pant Publication No. 2014-091366 discloses a control device for a hybrid vehicle. In order to generate the engine output usable for power generation during the pre-stoppage self-sustaining operation, this control device sets the ignition timing during the pre-stoppage self-sustaining operation control to timing earlier than in the normal self-sustaining operation.
However, in the above case, the change in the torque generated at the time of stopping the operation of the engine increases by the torque generated by the advancement ignition of the ignition timing. Therefore, there is a risk that the vibration of the vehicle due to the stoppage of the operation of the engine is not sufficiently suppressed.